Cardiopulmonary resuscitation (CPR) is used to maintain adequate perfusion of vital organs in cardiac arrest patients and is fundamental for the neurological outcome and survival of these individuals. Unfortunately, the quality of CPR may be inadequate due largely to ineffective chest compressions resulting from rescuer fatigue and interruptions in compressions. The LUCAS device (Lund University Cardiopulmonary Assist System, Jolife, Lund, Sweden), introduced in 2002, is the most extensively tested and applied automated alternative to manual CPR for in-hospital care of cardiac arrest patients and during ambulance transfer; the feasibility of application of this device in helicopter emergency medical service (HEMS) operations, however, has never been addressed. The objective of this project is to equip the three active rescue helicopters in South Tyrol with the LUCAS 2 mechanical chest compression device to answer the question: What is the feasibility and efficiency of using this device for prolonged CPR in cardiac arrest patients requiring CPR during HEMS rescue operations and transport?